Draw a 'star' pattern on the floor so you have a plus and two diagonals backwards. Alternatively you can use a tiled floor. Standing on one foot, reach in each marked direction with the other foot - tapping your toes forward, backward, left, right and then backward left and backward right - all without weightbearing on the reaching foot. The aim to to get as far as you can whilst maintaining good knee alignment and stability. Repeat this as many times as you can for endurance and strengthening